Thomas Jefferson Papers

To Thomas Jefferson from Albert Gallatin, 22 January 1808

on or before 22 Jan. 1808


Plan proposed by Dorsey; to which add abolishing the troy weight & substituting the division of the avordupoids ounce (or cubic decime of foot) into either 1000 parts. (or into 20 penny weights & each penny wt. into 24 grains.) The avordupoids pound being equal to 7000 troy grains, the ounce is equal to 437½ troy grains. Our unit of money or dollar contains 371¼ troy grains of pure silver & is by a small fraction of a cent worth less than the Spanish dollar. Raising it to 371 troy grains (or 1/6th of a cent) will make it precisely equal to 850/1000 parts of the avordupoids ounce. The alloy is now 44¾ grains (making the weight of the dollar in standard silver 416 troy grains). Making it 43¾ troy grains will make it equal to 10/1000 parts of the avordupoids ounce, & the weight of the dollar 950/1000 parts of do. (or 415 troy grains).

It follows that the subdivision of the avordupoids ounce may be advantageously substituted to the troy weight; & that we will have more eligible numbers to express the weight of our money unit either in pure silver or true value, or in standard silver.

As to gold, as it is now rated by law as 15: to 1 in relation to silver; the eagle must contain in pure gold of the weight of the pure silver in a dollar, vizt. 247½ troy grains = 566/1000 + 2/3000 parts of the ounce avordupoids. But if you divide that ounce into 20 penny wts., each to contain 24 grains; then the pure gold in the eagle would weigh 11 such penny weights & 8 grains or 272 such grains. But that valuation of gold is arbitrary & really too low. Though it varies, it may be estimated at present, as in the French monetary system, at 15½. Putting it at 15 5/11, would make the weight of pure gold in the eagle = 550/1000 parts of the avordupoids ounce; & preserving the same standard or 22 carats would make the alloy in the eagle weigh 50/1000 parts of the avordupoids ounce &, the whole eagle 600/1000 or 3/5 of said ounce. That change in the value of gold, which is the only one proposed would make the eagles now in circulation worth 10 dollars & 33 cents. If that be thought ineligible other modifications may be adopted making a smaller change but leaving still round numbers.


On Dorsey’s plan, we must first fix an arbitrary foot vizt. what we call the English foot, and hereafter compare it with our future standard derived either from pendular or length of a degree of latitude. This may not be objectionable as the foot or unit we will now fix will be in some one certain ratio to the permanent standard to be hereafter fixed & may always be ascertained by reference thereto.

But there is an objection arising from the cubic foot not being precisely equal to some of the powers of the unit of weight & measure of capacity. This may be remedied by either encreasing the foot about 1/126th part; or by diminishing the pound & pint 3/128 or about 1/43 part.

On either plan the foot would be divided into eights instead of tenths, containing 512 (instead of 1000) equal parts; each part equal to the th part of a pound or pint; so that

the whole cubic foot would be = to 64w or a bushel
the ½ do or 256 cubic 8ths/parts = 32w or ½ bushel
the ¼ do or 128 parts = 16w or a peck
the do or 64 parts = 8w or a gallon
the 1/16 do or 32 parts = 4w or ½ gallon
the 1/32 do or 16 parts = 2w or quart
the 1/64 do or 8 parts = 1w or pint
the 1/128 do or 4 do = ½w or ½ pint
the 1/256 do or 2 do = ¼w or jill
the 1/512 do or 1 do = w or ½ jill
the 1/1024 do or ½ do = ounce or ¼ jill

But would the advantage resulting from that regular & uniform division balance the inconvenience of the alteration in either the foot, or pound & pint? and, if an alteration be made, which would be lest inconvenient, the increase of the foot or the decrease of weights & measures of capacity? I think that I had rather increase the foot.

DLC: Papers of Thomas Jefferson.

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